Diffusion and Osmosis

Diffusion

Movement of molecules down a concentration gradient

Osmosis

Diffusion of water across a semipermeable membrane

Passive transport

Movement of molecules without energy input

Concentration gradient

Difference in concentration of a substance between locations

Isotonic solution

Solution with equal solute concentration compared to another solution

Hypertonic solution

Solution with higher solute concentration compared to another solution

Hypotonic solution

Solution with lower solute concentration compared to another solution

Facilitated diffusion

Diffusion through transport proteins

Transport proteins

Proteins that help molecules cross the cell membrane

Gas exchange

Diffusion of gases in the lungs and blood

Absorption of water by plant roots

Process using osmosis

Absorption of water in small intestine and colon

Process using osmosis

Comparative solutions

Isotonic, hypertonic, or hypotonic solutions compared to each other

Draw arrow indicating water movement

Determining water movement based on solute ratio

Transport proteins

Proteins that help molecules cross the cell membrane

Glucose

Example of molecule transported through facilitated diffusion